Between 2002-2012, the NIDDK sponsored Phases 1 and 2 of the prospective Chronic Renal Insufficiency Cohort (CRIC) Study, which enrolled >3,900 adults with chronic kidney disease at seven Clinical Centers to address the overarching goals of identifying risk factors for kidney disease progression and clarifying the relationship between renal dysfunction and the risks of subclinical and clinical cardiovascular events, death, and resource utilization. The initial five-year follow-up of Phase 1 was extended by an additional five years in Phase 2, which ends April 2013. The proposed CRIC-Phase 3 offers a unique opportunity to leverage the existing effort and success of CRIC by extending the follow-up for the existing cohort to June 2018; by recruiting and following a new cohort of 1,500 individuals with less severe CKD; and by evaluating a more comprehensive set of exposures and outcomes. CRIC-Phase 3 will become an unparalleled resource that will expand the science related to chronic kidney disease natural history as well as the impact of kidney dysfunction on the development and progression of cardiovascular disease and other adverse events. Specific Aims to be addressed by the Kaiser Permanente Northern California/University of California, San Francisco Clinical Center are: 1. To re-enroll a high percentage of CRIC-Phase 1 participants into CRIC-Phase 3. 2. To recruit and enroll an additional cohort of 215 participants with less severe CKD into CRIC-Phase 3. 3. To collect exposure and outcome data per the CRIC-Phase 3 protocol.4.To maintain high levels of retention in the study. 5. To investigate clinical events and obtain supporting medical records and documentation. 6. To enter data and process/ship biological specimens. 7. To implement local quality assurance and quality control procedures as a means to obtain standardized, high quality measurements. 8. To monitor data collection, data entry, and follow-up rates. 9. To participate in governance and oversight of CRIC through study-wide subcommittees and activities. 10. To publish and present findings from the CRIC Study. 11. To promote and support the conduct of ancillary studies in CRIC, including collaboration with the broader nephrology research community.